I totally agree with you. If you pay close attention during the end credits of Guardians of the Galaxy you can see Howard the Duck and Adam's cocoon open. Not to mention, the new movie Guardians of the Galaxy 2 is coming out May 5th of 2017. What could the plot be this time? Maybe Starlord finally searches for and discovers his father.
The next movie to follow the next year is Infinity Wars and one of the main guys to defeat Thanos is Adam Warlock. If they introduce him as Quil's father in GOTG2 that makes it much easier to have him introduced in the Infinity Wars.